Currently, combines typically include a crop residue spreader for disposing of straw and other residue separated from the harvested crop onto the field from which the crop was harvested. In addition, some combines have a chaff spreader for spreading chaff residue separated from the grain by the cleaning apparatus or system onto the crop field. In many instances it is desirable for the straw, chaff and other residue to be spread as evenly as possible over the width or swath of that section of the field over which the combine has just passed and harvested the crop from, to avoid problems resulting from uneven spreading, such as, but not limited to, difficulty in passage of fall tillage tools through residue clumps or thick areas; uneven insulation of the field resulting in uneven field warming and thawing and crop emergence during the following planting season; and increased rodent and insect habitat. In some instances, it is also desirable to have an ability to adjust the spreading to compensate for crop type, varying moisture and weather conditions, such as wind and the like, and also combine header width.
Although various crop residue spreaders are known which can propel residue a distance equal to about one half the width of a typical combine header, many suffer from shortcomings, including a tendency to provide uneven crop residue distribution or coverage in the side to side direction over the swath. More particularly, for a vertical spreader, that is, a spreader utilizing one or more rotary impellers or other elements rotatable about a generally horizontal axis, or an axis oriented or tilted at a small acute angle to horizontal, and configured for directing a flow or flows of crop residue sidewardly, it has been found that the resultant coverage has a tendency to be uneven in the sideward direction, for instance, typically thicker toward the outer regions or sides of the swath, and thinner or less uniform closer to the center of the swath.
Thus, what is sought is a crop residue flow distributor for a crop residue spreader, having a capability to adjustably distribute or guide portions of a discharged flow of crop residue for achieving a desired pattern of the distributed residue, which can include particularly, more even distribution side to side over a region of an agricultural field from which the crop was harvested, to achieve the advantages, and overcome one or more of the shortcomings and limitations set forth above.
Various conditions, such as wind condition, can affect crop residue flow and distribution over a field, which conditions, particularly wind direction, speed, etc., can change, often virtually continuously due to atmospheric conditions and the like, and also due to directional changes of the combine itself, for example, harvesting in head lands and traversing swaths of a field in different directions. In addition, field condition and crop characteristics, such as moisture content and crop population, can affect crop residue flow and distribution and can change as swaths of a field are harvested. Swaths with a higher moisture content and denser crop population would not have the same crop residue distribution pattern as swaths with a lower moisture content and sparser crop population. These conditions can make having a capability to change crop residue discharge flow, easily, and on the go, essential to achieving the desired residue spread.